1. Field of the Invention
The present invention relates to a cord connection structure for connecting a starter circuit to a ballast circuit, both components being necessary for lighting a discharge bulb as a light source of the headlamps for an automobile.
2. Related Art
As bulbs for automobile headlamps, discharge bulbs recently have attracted much attention because of their high luminous intensity and high durability. When the discharge bulb is employed as a light source of the headlamp, a starter circuit and a ballast circuit must also be provided; the former is for starting the discharge bulb and the latter is for securing stable and continuous lighting of the discharge bulb. FIG. 20 is a partial cross sectional view showing a proposed cord connection structure. As shown, a discharge bulb 2 is inserted into a bulb insertion hole 1a of a reflector 1. A starter circuit unit 5 is mounted at an opening 4 of a lamp body 3. The mounting and removing operations of the discharge bulb are carried out through the opening. A ballast circuit unit 6, fixed to the car body B, is disposed near the starter circuit unit 5. The starter circuit unit 5 is connected through output cords 5a to the discharge bulb 2. The starter circuit unit 5 and the ballast circuit unit 6 respectively include a case containing therein a starter circuit and a case containing therein a ballast circuit. The circuits are connected to each other by an output cord 7. The output cord 7 extends from the ballast circuit unit 6. A connector 8 attached to one end of the output cord 7 can easily be connected to and disconnected from the connector connection part 9 of the starter circuit unit 5. In the cord connection structure for connecting the starter circuit unit to the ballast circuit unit, both the circuits 5 and 6 are connected in such a manner that the headlamp bearing the starter circuit unit 5 on the rear side thereof is mounted on a car body, the ballast circuit unit 6 is fixed to the car body, and the connector 8 is coupled to the connector connection part 9. In this respect, the cord connection structure is excellent in assembly to the car body.
However, the proposed cord connection structure as described above may suffer from a problem as follows. When the discharge bulb 2 is actuated, a high voltage is applied to the output cord 7 connecting the starter circuit unit 5 to the ballast circuit unit 6. Such a structure allows any person to touch carelessly the connector 8 for the purpose of removing the connector, which is very dangerous because of the high voltage.